The city of Thessaloniki, the second largest city in Greece, joined the Covenant of Mayors initiative in 2011, committing itself to increasing energy efficiency and the use of renewable energy sources. The city suffers extreme temperatures, extended heatwaves and water scarcity as well as the threat of flooding during extreme rainfall.

Beyond water management and heat stress reduction, greening the city contributes to reducing air and noise pollution, increasing biodiversity, and capturing CO2. Thessaloniki’s green plan, adopted in 2017, acknowledges these environmental and ecological benefits. But in many cases, those benefits are barely known and not easy to quantify.

The project aims to retrofit part of the declining historical centre and modify the microclimatic conditions of this area, especially during the summer period, to protect the vulnerable population from heat and to reduce the energy consumption of buildings with the use of modern materials.

The project commenced in July 2014 and was delivered to the public in March 2016: the renovation was implemented in close cooperation with all stakeholders and utility companies.

The study for reformation of the project area in the historic centre was prepared by the municipal buildings and open spaces studies department of the Municipality of Thessaloniki. The project includes the bioclimatic upgrade of Chrimatistiriou (Stock Exchange) Square and a significant portion of the old commercial and business centre of Thessaloniki, a total area of approximately 107,000 m2.

Various interventions have been conducted, such as coating objects with cold materials, installation of bioclimatic systems promoting water evaporation (water jets, water curtains and sprinklers) and forced air movement (through use of outdoor fans), installation of new lighting equipment and creation of a pedestrian network as well as tree planting. In the middle of Emporiou (Trade) square, a big suspended fan hanging from an arch ensures a mild airflow that reaches up to the surrounding buildings and cools down the space. Moreover, part of Emporiou Square has been covered with new stabilised ecological material. In Emporiou street, the pavements have been widened and protected with barriers along their entire length, trees planted and new urban equipment such as benches, bicycle racks and new lamp posts make the street more liveable and accessible to disabled people. A pedestrian network was created, exceptionally allowing the use of emergency vehicles as well as commercial vehicles for loading and unloading at certain times of the day.

In order to manage the large amount of waste produced in the area during the project, the infrastructure for the installation of high capacity submerged bins was completed. Several private buildings in the area were retrofitted by their owners and converted from storage sites into spaces for other functions such as offices, residences, education and recreation premises.

The lead agency for the project is the City of Thessaloniki. The project’s budget amounts to approximately €5,500,000 and was financed by the National Strategic Reference Framework 2007-2013 (the programme under which EU structural funding is implemented in Greece).

This initiative has already proved multiple benefits.

• The project generated an estimated air temperature reduction of 3°C, which has resulted in energy savings of approximately 141 MWh/year and CO2 reduction of approximately 156 tonnes/year, by reducing reliance on air-conditioning.
• The upgrade of the city centre area should also lead to a stimulation of commercial activities, provide a feeling of security and contribute to the visibility of the history and cultural heritage of the city.
• Moreover, the area is now more accessible by people with disabilities and the renovation prevents the transit of a large number of vehicles. Permanent parking of vehicles is also prohibited, but the area includes temporary parking spaces in particular for loading and unloading.
• Furthermore, a Cultural Route has been created to highlight the historical significance of the area and the preserved buildings.

Covenant of Mayors case study: http://nws.eurocities.eu/MediaShell/media/CoM_Thessaloniki_EN.pdf